New plywood nailed to an old roof deck

The roofing company nailed the new plywood as the pictures show. Please could you tell me if it is installed correctly?

Hell no! Not in my opinion! I skim coat old roof decks all the time with new plywood & I use liquid nail & ringshank nails. We snap lines & nail into the rafters. It doesn’t appear that your guy did it my way. Are the nails smooth or do they have rings around them?

As far as I am aware sheeting nails have to be driven into solid lumber (2x4, 2x6, etc). Are these sheets going to blow off, 99% they won’t.

Roofing Contractors Association of British Columbia (RCABC) wants 72 nails per sheet of plywood/osb, driven into solid timber.

I’m with bcdemon. Yes the proper thing to do would have been to break the plywood seams on the rafters however I thing the chances of you ever having issues with it are extremely slim. Your old roof deck looks like it was in great shape so I suspect those nails have pretty good holding power.

Why were they installing plywood to begin with? Your existing roof deck looks ok from what i can see except the one piece that needed replaced.

It’s ok to install plywood over an existing deck. However, the bad boards should be replaced first, the breaks/ends of the plywood should fall on the rafters and all nails should be driven into the rafters.

There is a little thing called a chalk line that makes this a fairly simple process.

Plus the exposed spikes sticking through everywhere looks like hell.

Thanks for your replies. My concern is: should I call them back to redo it through a warranty or is it good for the next 50 years? I did it with a quite well known company assuming they should know what they are doing, but was very unpleasantly surprised with the outcome. Is there anything that would give me leverage to call them back and get them to redo it from the beginning? It’s a lot of money I paid for it ($15k).

You gotta wonder that if they didn’t care enough to put the nails in the rafters what else did they blow through while not giving a crap about what they were doing?

I would be concerned about the rest of the roof.
I mean like it was stated above, it’s pretty easy to snap a chalk line to hit some rafters and they didn’t care enough about what they were doing to even do that, and this is kinda important.
What about all the little things that aren’t so important?

I’ve seen it many times, the ends of the plywood will likely start to lift because they aren’t nailed into the rafters.

If you bought an asphalt shingle roof don’t expect it to last (looking decent anyway) for any more than 30 yrs max, more like 25 if done right.
20 yrs or less if it is one of the shingles that isn’t quite as good as it should be.

This isn’t what you want to hear I’m sure but I doubt you will have much luck getting them to replace the whole roof, esp if you already paid them. Most likely they will say something along the lines of “we’ve been doing it that way for 20 years and never had an issue”. They may offer to go up in the attic and bend the nails tight with the roof deck so they can’t back out. Only advise I can give you is to contact the manufacturer of the shingles and see if they’ll send a rep out to inspect the job.

Ouch! I forgot to mention it: it’s a flat roof with a slope about 1:30. From above, it looks very nice, though.